Arduinos are a great introduction to microcontrollers for starting electronics hobbyists.
They are plug-and-play development environments that can introduce a plethora of
topics about electronics, awesome right! The main model produced by Arduino,
called the Arduino Uno, uses the Atmel 328P Microcontroller as the main brain
on-board. Its stock package type is a large 28-pin DIP package. Very large and
gives an excess of I/O pins that won’t be utilized in many projects. Atmel produces
other smaller sized DIP package microcontrollers, the 14-pin Attiny84 and the
8-pin Attiny85 are two of the most popular.
The problem is that when you buy these microcontrollers from your distributer
they are not automatically ready to be given instruction sets. A bootloader must
be burned to these microcontroller chips before they are ready to be programmed.
Also, if you want to write programs to these microcontrollers you would have to
remove the stock 28-pin microcontroller every time you put a new chip in. This
will eventually lead you to damaging an IC chip.
A solution is to use an ISP (In-System Programmer) to burn the bootloader and
put your program on the chip. This can be done externally on a breadboard, but
that’s a hassle. You have to get the breadboard, jumper wires, and be sure that
you are hooking up to your main Arduino Uno unit every time (Here’s the article
on Arduino’s website describing this process in more depth: ArduinoISP).
Rather than doing that I made an Arduino Shield, which is just a separate
printed circuit board that sits on top of the Arduino Uno, that can program 28-pin
Atmel chips, 14-pin Atmel chips, and 8-pin Atmel chips. The shield was designed
in Eagle CAD and features three indicator LEDs that display when the chip is being
programmed, has an error, and Heartbeat (To show that the chip in responding normally).
The shield was marked with “Swallowtail Electronics” on top. This is a small
business I have started and am working on. More to come on that.
Here's the Bill Of Materials for this project
BOM Item # | Item Name | Quantity | Price/Unit | Total Cost |
---|---|---|---|---|
1 | PCB Manufacturing | 1 | $10.00 | |
2 | 220Ω Resistor | 3 | $0.05 | |
3 | 28-Pin DIP Socket | 1 | $0.50 | |
4 | 14-Pin DIP Socket | 1 | $0.50 | |
5 | 8-Pin DIP Socket | 1 | $0.50 | |
6 | 5MM LED | 3 | $0.75 | |
7 | 40ct. Male Header Pins | 1 | $1.00 | |
8 | 10µF Capacitor | 1 | $0.35 | |
$15.25 |